• Food Science of Animal Resources
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• v.28 no.1
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• pp.1-8
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• 2008

More safe and natural food was recently needed by consumers. Antimicrobials including sodium azide, penicillin, and vancomycin were used for therapeutic agents against pathogens such as Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7 in dairy and meat industry. These antimicrobials and preservatives were prohibited in stock farm and food because they were caused resistant strain and side effects. Bacteriocins are proteinaceous compounds that may present antimicrobial activity towards important food-borne pathogens and spoilage-related microflora. Therefore, bacteriocins were reported as an alternative of antimicrobials. Due to these properties, bacteriocin-producing strains or purified bacteriocins have a great potential of use in biologically based food preservation systems. Despite the growing number of articles regarding on the isolation of bacteriocinogenic strains, genetic determinants for production, purification and biochemical characterization of these inhibitory substances, there are only limited reports of successful application of bacteriocins to dairy and meats. This review describes bacteriocins related to dairy and meat products for the further use.

• Korean Journal of Materials Research
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• v.22 no.5
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• pp.243-248
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• 2012

ZrN nanoparticles were prepared by an exothermic reduction of $ZrCl_4$ with $NaN_3$ in the presence of NaCl flux in a nitrogen atmosphere. Using a solid-state combustion approach, we have demonstrated that the zirconium nitride nanoparticles synthesis process can be completed in only several minutes compared with a few hours for previous synthesis approaches. The chemistry of the combustion process is not complex and is based on a metathesis reaction between $ZrCl_4$ and $NaN_3$. Because of the low melting and boiling points of the raw materials it was possible to synthesize the ZrN phase at low combustion temperatures. It was shown that the combustion temperature and the size of the particles can be readily controlled by tuning the concentration of the NaCl flux. The results show that an increase in the NaCl concentration (from 2 to 13 M) results in a temperature decrease from 1280 to $750^{\circ}C$. ZrN nanoparticles have a high surface area (50-70 $m^2/g$), narrow pore size distribution, and nano-particle size between 10 and 30 nm. The activation energy, which can be extracted from the experimental combustion temperature data, is: E = 20 kcal/mol. The method reported here is self-sustaining, rapid, and can be scaled up for a large scale production of a transition metal nitride nanoparticle system (TiN, TaN, HfN, etc.) with suitable halide salts and alkali metal azide.

• The Korea Journal of Herbology
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• v.26 no.4
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• pp.67-74
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• 2011

Objectives : The purpose of the study is to determine the neuroprotective effects of the water extract of Angelicae Acutilobae Radix(AA) on ischemia reperfusion-induced apoptosis in SK-N-SH human brain neuronal cells. Methods: SK-N-SH cells were treated with different concentrations of AA water extract (0.1, 0.2, 0.5 and 1.0 mg/ml) for 2 hr and then stimulated with Dulbecco's phosphate-buffered saline containing CI-DPBS: 3mM sodium azide and 10 mM 2-deoxy-D-glucose for 45 min, reperfused with growth medium, and incubated for 24 h. Cell viability was determined by WST-1 assay, and ATP/ADP levels were measured by ADP/ATP ratio assay kit. The levels of caspase-3 protein were determined by Western blot and apoptotic body was observed by Hoechst 33258 staining. Results : AA extract significantly inhibited decreasing the cell viability in ischemia-induced SK-N-SH cells. AA also increased the ratio of ADP/ATP in ischemia-induced neuronal cells and decreased the expression levels of apoptotic protein, caspase-3 and apoptotic DNA damage. Conclusions : Our results suggest that AA extract has a neuroprotective property via suppressing the apoptosis and increasing the energy levels in neuronal cells, suggesting that AA extract may has a therapeutic potential in the treatment of ischemic brain injury.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.46-51
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• 2008

In this study, the antioxidant and antimutagenic activities of Cuscutae semen ethanol extract were evaluated. Antioxidant activity was measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method and the Ames test was employed to determine the inhibition effect on mutagenicity in Salmonella typhimurium TA100. The extract showed significant free radical-scavenging activity towards the DPPH radical, and at a concentration of 400 ppm, its free radical-scavenging activity was similar to that of BHT. The $IC_{50}$ value of the extract was 89 ppm, indicating good antioxidant capacity. Moreover, at 5 mg/mL, the extract presented inhibitions of approximately 98.0% and 49.2% on mutagenicity induced by 4-nitroquinoline 1-oxide and sodium azide, respectively. The total polyphenols and flavonoid contents of the extract were 20.1 mg/g and 1.9 mg/g, respectively. Therefore, this study indicates that the ethanolic extract of Cuscutae semen has excellent antioxidative and antimutagenic potential.

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.844-850
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• 2000

The specific binding and internalization of viral particles is an essential step for the successful infection of viral pathogens. In the case of the hepatitis B virus (HBV), virions bind to the host cell via the preS domain of the viral surface antigen and are subsequently internalized by endocytosis. HBV-preS specific receptors are primarily expressed on hepatocytes, however, viral DNA and proteins have also been detected in extrahepatic sites, suggsting that celluar recepators for HBV may also exist on extrahepatic cells. Recently, an EBV-transformed B-cell line was identified onto which the preS region binds in a receptor-ligand specific manner. In this study, this specific interaction was further characterized, and the binding region within the preS protein was locaized. Also the internalization after host cell attachment was visualized and analyzed by fluorescence-labeled HBV-preS1 proteins using confocal microscopy. Energy depletion by sodium azide treatment effectively inhibited the internalization of the membrane-bound preS1 ligands, thereby indicating an energy-dependent receptor-mediated endocytotic pathway. Accordingly, the interaction of HBV-pres! with this specific B-cell line may serve as an effective model for an infection pathway in extrahepatic cells.

• The Journal of Natural Sciences
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• v.7
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• pp.47-51
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• 1995

In order to develope new asymmetric catalyst, we synthesized the following new sulfonamide derivatives start from S-Indoline-2-Carboxylic Acid via the following 5 steps. Hydroxy methyl derivative(1) was thus treated with methane sulfonyl chloride in the presence of triethylamine as base to give mesylated derivative(2) in 85% of isolated yield. The mesylate compound (2) was treated with excess sodium azide to give Azido derivative (4) in 95% isolated yield. Azido compound (3) was then reduced to the corresponding amino derivative in near quntitative yield by the hydrogenation under hydrogen atmospere in the presence of catalytic amount of Pd-C. The amino derivative (4) was converted to its sulfonamide derivatives by the treatment of compound(4) with triisopropyl benzene sulfonyl chloride in the presence of triethyl amine as base. Finally t-BOC group of the compound(5) was removed by the treatement of excess Trifluoro-acetic acid in near quantitative yield to give the target sulfonamide derivative (7) .in this paper we prepared compound(6) in 49% overall yield via the 5 steps of synthesis starting from t-Boc- 2-hydroxy methyl indoline(1) which cab be easily prepared from commercial available S-indoline-2-carboxylic acid by known methods. we plan to apply this new catalyst for the asymmetric reduction , diels-alder reaction, aldolcondensation reaction in due courses.

• The Korea Journal of Herbology
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• v.25 no.2
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• pp.137-144
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• 2010

Objectives : We investigated genetic toxicity of HMCO5 using the Micronucleus Test in bone marrow cells of mice and Bacterial Reverse Mutation Assay in plate incorporation method according to OECD Guidelines and KFDA Guidelines. Methods : 1. Micronucleus test: The male rats were divided into 5 groups, respectively; G(1), treated with distilled water: G(2), treated with 1250mg/kg HMC05: G(3), treated with 2500mg/kg HMC05, G(4), treated with 5,000mg/kg HMC05; G(5), treated with Cyclophosphamide $H_2O$. Sterilized distilled water and HMC05 were administered for two consecutive days. Cyclophosphamide $H_2O$ was administered once on the day of 2nd administration. 2. Bacterial Reverse Mutation Aassay: Experimental groups were divided into two groups: with S-9mix(+S) or without S-9mix(-S). Each group treated with sterilized distilled water only, HMCO5(62, 185, 556, 1,667, $5,000{\mu}g$/plate) and, positive vehicles(Sodium azide, 2-Aminoanthracene, 4-Nitroquinoline N-oxide, ICR 191), respectively. Results : HMC05 did not show any changes in the number of micronucleated polychromatic erythrocytes(MNPCE) among 200 polychromatic erythrocytes compare to negative control. However, there were significant (p<0.01) increase with CPA in MNPCE. In Bacterial Reverse Mutation Aassay, no significant increases in the number of revertant colonies compared to (삭제) negative control were detected in all concentrations of HMC05. Conclusions : These results indicate that HMC05 did not show any genotoxicity against in Micronucleus test and Bacterial Reverse Mutation Aassay.

• The Plant Pathology Journal
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• v.21 no.4
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• pp.301-309
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• 2005

Trichoderma species/isolates exhibited varied degree of agglutination on sclerotial (Sc) and hyphal (Hy) surface of Macrophomina phaseolina. The agglutination efficiencies on Sc and Hy ranged from $11\;to\;57\%$. Isolates of T. harzianum (Th) and T. viride (Tv) showed greater agglutination on Sc ($23-57\%$) and Hy ($16-47\%$). Different enzymes (trypsin, pepsin, proteinase k, a-chymotrypsin, lyticase and glucosidase) and inhibitors (tunicamycin, cycloheximide, brefeldin A, sodium azide, dithiothreitol and SDS) reduced the agglutination potential of conidia of Th-23/98 and Tv-25/98; however, the extent of response varied greatly in different treatments. Different fractions of Th-23/98 and Tv-25/98 exhibited haemagglutinating reaction with human blood group A, B, AB and O. Haemagglutinating activity was inhibited by different sugars and glycoproteins tested. Crude haemagglutinating protein from outer cell wall protein fraction of Th-23/98 and Tv-25/98 were eluted on Sephadex G-100 column. Initially Th-23/98 and Tv-25/98 exhibited two peaks showing no agglutination activity; however, lectin activity was detected in the third peak. Similar to crude lectin, the purified lectin also exhibited haemagglutinating activity with different erythrocyte source. SDS-PAGE analysis of partially purified lectin revealed single band with an estimated molecular mass of 55 and 52 kDa in Th-23/98 and Tv-25/98, respectively. Trypsin, chymotrypsin and b-1,3-glucanase totally inhibited lectin activity. Similarly, various pH also affected the haemagglutinating activity of Th-23/98 and Tv-25/98. From the present observations, it can be concluded that the recognition/attachment of mycoparasite (T. harzianum and T. viride) to the host surface (M. phaseolina) may be most likely due to lectin-carbohydrate interaction.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.125-130
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• 2006

The emergence of extended spectrum ${\beta}$-lactamase producing bacteria is causing very serious problems in Korea. Although there have been many reports about these bacteria Isolated from patients and clinical specimens, there is no report of extended spectrum ${\beta}$-lactamase producing organisms isolated from natural environment in Korea. This study was conducted to investigate the biological characteristics and extended spectrum ${\beta}$-lactamase types of eighteen strains of extended spectrum ${\beta}$-lactamase producing Klebsiella pneumoniae and Escherichia coli isolated from a slaughterhouse in Pusan in Korea during 2002 to 2004. Extended spectrum ${\beta}$-lactamases were identified by double-disk synergy test, conjugation, isoelectric focusing values and gene sequencing. Eight strains of Klebsiella pneumoniae and two strains of Eschericha coli were isolated kom pigs and transferred extended spectrum ${\beta}$-lactamase genes to recipient Escherichia coli J53 (sodium azide resistant and ceftazidime senstive) strain by conjugation. The conjugants of extended spectrum ${\beta}$-lactamase genes were alignments and translated to amino acids by BCM and NCBI blast. Eight conjugants of Klebsiella pneumonae were typed TEM-52, and two strains of Escherichia coli, SHV-12, but CMY-1 type were not detected in this study.

• The Korea Journal of Herbology
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• v.28 no.2
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• pp.45-53
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• 2013

Objectives : The purpose of the study is to determine the neuroprotective effects of the water and 80% EtOH extract of some herbal medicine plant on ischemia reperfusion-induced cell death in SK-N-SH human brain neuronal cells. Methods : SK-N-SH cells were treated with 3mM sodium azide and 10 mM 2-deoxy-D-glucose for 45 min, ptior to the addition of different concentrations of herbal medicine plant extract (0, 10, 25, 50, 100, 250, 500, 1000 ${\mu}g/ml$) for 2 hr and then reperfused with growth medium, incubated for 24 h. Cell viability was determined by WST-1 assay, and ATP/ADP levels were measured by ADP/ATP ratio assay kit. Results : Herbal medicine plant extract significantly inhibited decreasing the cell viability in ischemia-induced SK-N-SH cells. Also increased the ratio of ADP/ATP in ischemia-induced neuronal cells. Conclusions : Our results suggest that herbal medicine plant extract has a neuroprotective property via increasing the energy levels in neuronal cells, suggesting that extract may has a therapeutic potential in the treatment of ischemic brain injury. The exact component and mechanism remains for the future study.